Liquid heater



Jan. 22, 1929. 1,699,919

o. PROLLIUS LIQUID HEATER Filed ov. 5, 1924 2 Sheets-Sheet l I PatentedJam. 22, 1929.

UNITED STATES;

PATENT OFFICE.

OTTO PROLLIUS, OF BEBGEDOBF, HAMBITRG, GERMANY, ASSIGNQR TO THE EIRMIBEBGEDOBFEB EISEN'WERK, AKTIENGESELLSCHAIT,' 01's SAUDE, NEAR BEBGEDOBF,GERMANY.

mourn mum.

Application filed November 3,1924, Serial No. 747,592, in Germany May16, 1924.

My invention relates to liquid heaters and more particularly to a heaterin which the liquid trickles down a plurality of superimposed heatingelements which may be tubular 5 and heated on the inside'by water ofsuitable temperature.

' Heaters of this kind are as a rule employed in the heating of milk orother liquids which contain gases in solution.

.I-Ieaters of this type involve the drawback that a very considerableloss by evaporation is incurred at high temperature. *In order toovercome this drawback it has been proposed to provide such heaters withjackets adapted "1 to collect the vapors. With this expedient howeveranother drawback is connected, viz, the gases are retained in theliquid. It is Well known that a liquid such as milk contains gases insolution and also readily absorbs air. It is therefore necessary toremove these gases before the final heating of the liquid. Obviouslythis is impossible if the heater is jacketed. Milk heated in. suchjacketed devices is not satisfactory and particularly lacks flavour.

These drawbacks are overcome according to my invention by subdividingthe'irrigation heater into several groups, for instance two, one ofwhich serves for the preliminary heating of the milk and is unjacketed,while the other grou in which the milk is finally heated to a hig ertemperature, is surrounded by a jacket which collects the vapours asdescribed. When the milk trickles down the group, the gases dissolved init are liberated under the influence of the elevated tem- "perature ofthe heating elements practically without any evaporation taking placewhile in the second group where the milk is finally 40 heate d to ahigher temperature and intense evaporation occurs, *losses are preventedby the jacket.

In the drawings aflixed to this specification and forming part thereof aheater embodying my invention is illustrated diagrammatically by way ofexample.

Inthe drawings; v Fig. 1 is a vertical cross section, and V Fig. 2 is alongitudinal section on the line 5022ofFig.1. y

The heater comprises a plurality of tubular 5 superposed heatingelements h which are subdivided into two groups I and-IL The ends of theelements in each group are connected with heating chambers a and b. Thechambers are subdivided into compartments of two elements each bypartitions m which are arranged in staggered relation on opposite endsof the heater so that the heating medium which enters the heatingchamber a at the bottom through a pipe n, is conducted through thetubular elements h of the groups I and II in a zigzag path, anddischarged through a pipe 0 at the top of the heating chamber 6.

The medium obviously transfers part of its heat to the liquid so thatthe temperature gradually decreases from the bottom to the top of theapparatus and the liquid is accordinglysubjected to gradual heating, thehottest zone being at the bottom of the group III The pitch of thetubular elements it is extended where the groups I and II'adjoin, and atthis point a dlstributing vessel 0 is arranged between the two groupsand provided with a bottom in the shape of an inverted V, perforations 9being provided at either side of the V-shaped portion so that the milkor other liquid trickles down on both sides of the heating elements. Asimilar vessel 03 which also comprises a bottom at in the shape of theletter W in cross section, and'having perforations 1' at either sideabove the top heating element It, isarranged at the top of group I. Thefirst and last heating element of each group is provided with adeflecting rib h at its top and bottom respectively, which serves 'forguiding the liquid on its way down the heating elements., The lowergroup II is surrounded by a jacket g, 9 A third collecting tank 0 isarranged at the bottom of the second group a and provided with adischarge pipe 7. The heater is mounted on a foundation plate 1' andisrovided with cover plates k at both ends.

he operation of the heater is as follows: The heating medium such as hotwater, is

supplied to the elements of the first group I V temperature is not highenough to cause evaporation on the other hand the gases dissolvedtherein are liberated and the condition of the milkis improved.

From the collecting tank 0 the milk reaches the tubes h of the secondgroup II in Which water of higher temperature is circulating. Here themilk is part-1y evaporated, but, as the elements of this stage areentirely encased in the jacket g, 9 the vapors formed cannot escape butare condensed at the walls of the jacket and recovered so that theexcessive losses heretofore involved are avoided;

Obviously I may treat in the manner described any liquid other than milkand I may provide any number of groups or stages for the priliminary andfor the final heating of the liquid.

I Wish it to be understood that I do not desire to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

I claim Liquid heater comprising two' superposed groups of tubularheating elements arranged in series in the path of the liquid to beheated, thesuriace of the upper group being open to the air, and ajacket enclosing the lower group. r

In testimony whereof I afiix my signature.

OTTO PROLLIUS.

